Thursday, June 11, 2009

A Bird that is faster than Jets

A bird that outpaces a Jet sounds unbelievable and has the feel of a leaf out of science fiction. But it is true. During courtship flights, male Anna's hummingbirds sustain accelerations that would put to shame a fighter pilot.

Chris Clark, a biologist at the University of California used high-speed video footage to study the bird’s flight. His cameras were able to capture 500 frames per second. He has shown that, relative to their body size, Anna's hummingbirds are the fastest moving vertebrates.

And why does the bird push itself to such acrobatic displays? It is to impress the females during courtship. To impress the females, the males drop out of the sky in U-shaped flights and as they dive they travel nearly 400 times their body length each second. It is greater than the top speed of a fighter jet with its afterburners on, 885 metres per second, or the space shuttle during atmospheric re-entry, 7,700metres per second. . Centripetal accelerations reach 10 g, a force equivalent to 10 times the gravitational pull of Earth. Fighter jet pilots can pass out at accelerations above 7 g.

Clark used decoy stuffed models of female birds for his experiment. The males readily responded to the decoys.

Personally I am humbled by these mysteries of nature that is surfacing. We know so little about nature and still we are going all out to damage our environment. We have only scratched the surface.

The details of the amazing findings are reported in the journal Proceedings of the Royal Society B.